sql - Multiple ORDER BY (get latest element) MySQL -


i have following tables : radios, podcasts , shows. radio has many podcasts, , podcasts has many shows. each podcast can ordered history, , each show can ordered publication_date.

i want podcasts associated latest show.

the query looks : 

select r.name radio_name,pod.*,sh.*  podcasts pod    inner join radios r on (r.id=pod.radio_id)    inner join shows sh on (sh.podcast_id=pod.id)  order pod.history limit 5

i'd have second order sh.publication_date don't know should be.

if want latest show each pod cast, need information. here 1 method:

select r.name radio_name,pod.*,sh.*  podcasts pod inner join      radios r      on r.id = pod.radio_id inner join      shows sh      on sh.podcast_id = pod.id  not exists (select 1                   shows sh2                   sh2.podcast_id = sh.podcast_id.id ,                         sh2.publication_date > sh.publication_date                  ) order sh.publication_date desc limit 5;

in addition "obvious" indexes on join columns, walso want index on shows(podcast_id, publication_date).

i guessing want results ordered recent show publication date.


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